The invention relates generally to fluid-actuated clamping devices for releasably clamping an item in a predetermined position. More specifically, the present invention relates to such clamping devices adapted for horizontal or for vertical clamping engagement of such an item and having a clamping mechanism capable of being extended from, and retracted into, the body of the device.
Frequently, in a wide variety of applications, it is desired to forcibly clamp and hold an item in a predetermined position or location in order to perform a machining or fabrication operation thereon, for example. In such applications, the complexity of the shape or configuration of the item being clamped often presents difficulties in clamping the item, in providing access for a clamping member to engage the item, or in terms of portions of the clamping device interfering with other operations or functions prior or subsequent to the clamping operation. Thus, it has been found to be advantageous to provide clamping devices having clamping components or mechanisms that are capable of being extended either for horizontal or for vertical clamping engagement of the item and that can be retracted into the body of the device in order to clear the way for other operations or for moving the item to another location.
Accordingly, the present invention provides an improved, fluid-actuated retracting clamping device for releasably clamping an item in a predetermined position, with the clamping device including an elongated body having a fluid chamber therein, and with a movable armature disposed within the body of the clamping device and extending longitudinally in such fluid chamber. The fluid chamber includes a pair of fluid ports longitudinally spaced from one another in fluid communication with the fluid chamber, with a piston longitudinally fixed on the armature and sealingly disposed for slidable longitudinal movement within the fluid chamber, between the first fluid ports in order to selectively and forcibly extend and retract the armature longitudinally in response to respective greater and lesser fluid pressures in one of the fluid ports with respect to the other of the fluid ports.
A clamping sub-assembly attached to the armature is extendable from the body, and retractable into the body, and preferably includes a sleeve member, a clamping member, and linkage means interconnecting the sleeve member and the clamping member. The arrangement provides for pivotal movement of the clamping member relative to the sleeve member between a transversely-extending and generally longitudinally-aligned positions with respect to the armature. In various embodiments of the invention, the clamping members are capable of engaging the item to be clamped either horizontally or vertically, or in any other desired position.
Accordingly, the clamping device according to the present invention provides a very wide degree of flexibility in positioning the clamping device and the item to be clamped, in maneuvering the armature and clamping member, in accessing a desired clamping engagement location on an item, and in holding such item in a predetermined position with the clamping force being capable of being exerted in a wide variety of clamping directions. In addition, the articulating clamping member is preferably fully retractable into the body of the clamping device when the clamping function is not needed or desired. Furthermore, the clamping device of the present invention uses a toggle action to increase clamping force.
Additional objects, advantages, and features of the present invention will become apparent from the following description and the appended claims, taken in conjunction with the accompanying drawings.